Normal subjects and patients with suspected tearing disorders are to be evaluated in the Tear Film Laboratory with measurements which include recently developed microanalytic techniques for determining the composition and volume of basal tear secretion. Microsampling techniques will be utilized following a medication free time period to obtain microvolumes, one microliter or less, of basal tear secretions from the inferior marginal tear strip and inferior fornix. Subjective symptoms will be graded on a severity scale as well as slit lamp estimation of the inferior marginal tear strip size. The tear film will be examined by the biomicroscope for debri and increased viscoscity. Tear osmolarity by freezing point depression, lysozyme measurement by agar diffusion, lactoferrin analysis by rocket electrophoresis, and fluid volume measurements on 2 x 6 mm filter paper strips, Periopaper (R), placed in an electronic instrument, Periotron(R), will characterize basal secretion and inferior marginal tear strip composition in normals and patients with external ocular disease. Rose bengal staining and grading of severity will complete the laboratory examination. Analysis of the collected data will determine the average and range of values in basal tear secretions for these new microanalytic methods and will also determine their sensitivity and specificity in detecting patients with ocular disease.